The updated graphics work better for MI2 than MI1. That's because the MI2 graphics were scanned. (They even admit to that in the audio commentary.)

I just played the updated versions a few weeks ago. I'm a lifelong MI fan—I first played MI1 on my family's Tandy 1000 (16 colors and 3-voice sound!). I also was disappointed by MI1, which felt like a cheap money grab more than a faithful remake. The remake of MI2, OTOH, was a masterpiece—beautiful graphics and less clunky overall.

One really cool thing that both remakes offer is the ability to seamlessly switch between the remake and the original: At any point in the game, press the correct function key (F10 in MI1 and F1 in MI2—not sure why they switched that) and the game morphs between the remake and original without skipping a beat—down to the dialogue, music, etc. It didn't really add anything to gameplay, but it was really cool.